Dynamo-electric machine.



T. s. ALLEN. DYNAMO ELECTRIC MACHINE. APPLICATION FILED rii'B'izs, 1910.

1,085,31 6.- Patented J an. 27, 1:114.

high brush friction and contact losses. such machines considerable difficulty has UNITED snares PATENT OFFICE.

THOMAS ALLEN, OF MILWAUKEE, WISCONSIN, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO ALLIS-CHALMERS MANUFACTURING COMPANY, A CORPORATION- OF DELA- WARE.

DYNAMO-ELECTRIC MACHINE.

Specification of Letters Patent.

Application filed February 28, 1910. Serial No. 546,540.

To all whom it may concern.

Be it known that I, THOMAS S. ALLEN, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Dynamo- Electric Machines, of which the following is a full, clear, and exact specification.

This invention relates to dynamo-electric machines and particularly to improvements in the construction and means for cooling commutators of machines of high speed and large current outputsuch as turbo generators.

It is a well known fact that the commutators of high speed machines of large 'current output must be made relatively small in diameter, and that even though such commutators are given considerable length, the segments tend to become hot due to the In been experienced in supporting the segments in a manner such that they will not buckle or be distorted or otherwise shifted from position, and it has also been diflicult to cool the commutator in a satisfactory manner and to prevent a rise'in temperature which would affect the efiiciency and operation of the' commutator and brushes.

One of the objects of the invention is to provide commutator supporting means which permits a good circulation of air through the interior. of the commutator, which is very effective for securely holding .the segments in place, which is simple in construction,inexpensive to manufacture and assemble, and which permits an adjustment and a tightening of all the parts.

A further object is to secure a more effective cooling of a commutator than has been possible heretofore, so that the life of the commutator and brushes will be prolonged and their efficiency and operation will be improved.-

To the end of securing these and other objects hereinafter appearing, I have provided an improved construction, in carrying out my invention, consisting in certain novel details and combinations and arrangements of parts which will be described in the specification and set forth in the appended claims.

In the accompanying drawings, Figure l is a partial elevation and partial longitudinal sectional. view of a commutator constructed in accordance with my invention, and of a portion of the armature of a dynamo-electric machine; F ig. 2 is a transverse sectional view substantially along the line of Fig. 1, looking in the direction indicated by the arrow; Fig. 3 is a top plan view of a portion of the shaft and of the supporting means for the outer end of the commutator; and Fig. 4i is a sectional view taken through a portion of the combined commutator necks and fan blades.

Referring now to the figures of the drawing, 10 represents a portion of the armature, and 11 the shaft of a direct current dynamoelectric machine, such. as a turbo-generator or other directcurrent machine of large current output, having a long commutator, the segments of which are shown at 12.

In order that the segments may be supported in an effective and satisfactory manner, and so as to permit a good circulation of air through the interior of the commutator, I provide at the ends of the commutator two sets of supporting arms or members which project radially outward from the shaft. Preferably at the inner end of the commutator the supporting arms, which are shown at 13, are integral with the shaft and are formed by slotting-an inclined or tapered portion of the stock from which the shaft is formed, so that the arms have downwardly and outwardly tapered outer surfaces and air spaces 14 are formed between the arms.

At the outer end of the commutator the supporting arms are preferably adjustable and consist of wedges or tapered members 15 which have downwardly and inwardly tapered outer surfaces and are axially movable in slots 16 provided about the surface of the shaft. These members 15, which are spaced apart so that open air spaces are provided between them, may be shifted inwardly and are held securely in position after adjustment by nuts 17 which engage a threaded portion 18 of the shaft.

Resting on the outer tapered surfaces of the two sets of arms 13 and 15 respectively are tapered or conical'sleeves 19 and 20, which are preferably expansible, in this case each being split diagonally or provided with an inclined slot 21, so when the Wedges 15 are forced in by means of the nuts 17 the sleeves 20 and 19 will expand and grip the Patented Jan. 27,1914.

insulation 22 so that all the sliding movement will be between the metal sleeves 20,

l9 and the wedges 15, 13, thereby causing no displacement of the insulation 22. Jhe sleeves 19 and 20 support the segments 12 which are separated from the sleeves by suitable insulation 22, and which may he clamped to the sleeves and prevented. from buckling by any suitable clamping devices such as shrink rings 23, three of which are shown in the drawings. he portions of the inner surfaces of the segments opposite the sleeves are tapered or inclined in accordance with the inclination of the sleeves, so that the segments will be firmly seats and will be held against endwise movement. Because of the particular construction of the segment supporting means, air may circulate freely through the commutator between the arms 13 and between the arms 15 and along the inner surface of the com mutator between the segments and the shaft. In order that there may be a good continuous circulation of air through the interior of the commutator while the machine is in operation, any suitable ventilating means may be employed, but in this case I arrange the commutator necks 24 which connect the segments 12 and coils 25 of the armature winding, so that they will, in addition to carrying a current between the coils and the segments, act as fan blades. This is accomplished by skewing or inclining the blades with respect to the axis of the machine so that, when the machine is in operation and 'is'rotated in the direction indicated by the long arrow in Fig. 4, air will be drawn through the interior of the commutator from the outer to the inner end, and will be discharged in the direction indicated by the shorter arrows in Fig. 4 over the outer surface of the commutator. In this. manner the segments can be very effectively cooled.

Not only do the segment supporting means permit of a good circulation of air through the interior of the commutator, but, with the construction which I have provided, the segments are securely held in position, and the segments or supporting means can be adjusted, if adjustment is desired, because of the construction at the outer end of the commutator. Furthermore the commutator and the supporting means can be very easily assembled or taken apart when necessary.

I do not desire to be confined to the exact details shown, but aim in my claims to cover all modifications which do not involve a departure from the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent is 1. In combination, in a dynamoelectric machine, a shaft, a commutator comprising a plurality of segments, means for supporting the segments and spacing them from the shaft comprising two sets of arms win. spaces between the arms of each set, said spaces communicating freely through open ings large themselves with the between the shaft and the segments the atmosphere, sleeves resting on. the and forming seats for the segments, and means for clamping the segments to he sleeves.

2. In a commutator construction, a shaft,

outwardl from the shaft and provided with tapered outer surfaces, split tapered sleeves supported on the arms, each set of arms comprising a plurality of parallel, spaced and axially-disposed arms to provide through passage from one end of said commutator to the other beneath said segments, and means for clamping the segments onto the sleeves.

i. In a commutator construction, a sh a plurality .of commutator segments, l. for supporting the commutator at thereof, the supporting means at one er of the commutator comprising an int tapered portion of the shaft which is slo to forming supporting arms and air spaces between the arms, and a split conical sleeve resting on said arms and forming-a seat for the segments.

5. In a commutator construction, a pinrality of commutator segments, a shaft ea:- tending through the commutator, means for supporting the commutator so as provide an unobstructed passage between said com-- mutator segments and said shaft and co prising a plurality of independent, circr fer-entially-spaced, axially-movable tap members, an expansible sleeve supports b said members, and means for clamping the segments to said sleeve.

6. In a commutator construction, phi-- rality of segments, a shaft extend: g through the commutator and provided a plurality of axially t k, i rality of radially extending tapered members engaging said slots, an 'expansl sleeve supported on said members, and means for clamping the segments to the sleeve.

7. In combination, in a dynamoelectric machine, a shaft, a commutator comprising a plurality of segments, means for support ing the commutator at each end, sup porting means comprising two sets of rad-is arms with tapered outer one set boi g integral with the shaft, and the other set being supported thereby and adjustable in an axial direction, tapered expansible sleeves supported by the arms, and means for clamping the segments to the sleeves.

8. In combination, in a dynamo-electric machine, a shaft, a commutator comprising a plurality of segments, means for supporting the commutator at each end, said supporting means comprising two sets of out wardly projecting arms spaced apart by distances fully as wide as themselves, sleeves resting on the arms and having the segments clamped thereon, and means for causing a circulation of air' between the arms of each set and through the interior of the commutator. 1

9. In combination, in a dynamo-electric machine, a shaft, a commutator comprising a plurality of segments, means for supportin the segments so as to permit a free circu ation of air through the interior of the commutator, said supporting means cone prising two sets of members extending radially outward from the shaft adjacent opposite end of the commutator, the members of each set having air spaces between them, sleeves supported on said members and forming seats for the segments, rings surrounding the segments and clamping the latter to the sleeves, and means for causing a circulation of air through the air spaces between said members and through the interior of the commutator.

10. In a dynamo electric-machine, a commutator comprising a plurality of segments, a shaft, means for supporting said commutator segments on said shaft comprising a plurality of spaced wedge elements mounted on said shaft and an expansible ring encircling said elements, and means including skewed commutator leads for causing air to enter the space between the shaft and the commutator segments at one end of the commutator, to leave it at the other end, and then to pass along the outside of the commutator in the other direction.

u 11. In a. dynamo-electric machine, the combination of a shaft, an armature mounted thereon and provided with a winding, a commutator comprising a plurality of segments, supporting means for said segments comprising a plurality of spaced longitudinally extending elements mounted on said shaft adjacent said armature and an encircling ring on said elements, leads connecting said armature winding with said commutator segments, said commutator being spaccd from said shaft by said supporting elements to provide a passage between the end of said commutator adjacent said armature and another point along said commutator, and fan means associated with said leads for causing a flow of ventilating fluid axially beneath said commutator segments toward said armature and in the opposite direction across said commutator surface.

Milwaukee, \Visconsin, February 18, 1910. In testimony whereof I affix my signature, in the presence of two witnesses.

THOMAS S. ALLEN.

-Witnesses:

CHAS. L. BYRON. Ron. E. S'roLL.

It is hereby certified that, in Letters Patent No. 1,085,316, granted January 27,

1914, upon the application of Thomas S. Allen, of Milwaukee, Wisconsin, for an improvement in Dynamo-Electric Machines, an error appears in the printed specification requiring correction as follows: Page 3, line 25, for the word *end" read ends; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 17th day of February, A. D., 1914.

J. T. NEWTON,

Acting Gammissioner of Patents. 

